Photocopy developing apparatus



April 1, 1869 R. c. GoQnMAN ETAL 3,435,751

I Paa'rocoPY DEVELOPING APPARATUS Piled Nov-` s; 196e 2o y A20' F lgINVENToRs Robert C. Goodman v Emilio G. Mastroianni ATTORNEY UnitedStates Patent 3,435,751 PHOTOCOPY DEVELOPING APPARATUS Robert C.Goodman, Binghamton, and Emilio G. Mastroianni, Endicott, N.Y.,assignors to GAF Corporation, New York, N.Y., a corporation of DelawareFiled Nov. 3, 1966, Ser. No. 591,822 Int. Cl. G03d 3/12 U.S. Cl. 95-94 4Claims ABSTRACT OF THE DISCLOSURE A photographic apparatus having adeveloping chamber and a mixing chamber for anhydrous and aqueousammonia. A liquid vessel is connected to the mixing chamber and a pumpconnected to the liquid vessel establishes a predetermined liquid levelin the mixing chamber. A blower is in communication with the mixingchamber and circulates a solution into the developing chamber. A heatersystem is provided in the developing and mixing chambers to maintain theproper temperatureof the solution.

The present invention relates to developing apparatus and moreparticularly to such apparatus in which exposed, sensitized material iscontacted by a gaseous medium, such as an ammonia gas and water vapormixture.

Certain rerpoduction processes use ammonia gas and water vapor mixturesto develop exposed images on sensitized webs of lm, plastics, paper orother gelatin coated materials. Diiculties have been experienced withtransporting the material in the developing medium so that the materialis uniformly contacted by the developing medium without leavingscratches or marks thereon caused by supports for the material itself.Further the supply of the medium must be uniform, and the concentrationof the developing medium in the vapor phase, land its concentration withrespect to water vapor which is added thereto, must remain inpredetermined limits.

Briefly, in accordance with the present invention, the developingapparatus has a pair of chambers vertically spaced from one another. Amaterial such as sensitive paper, which has been exposed, is fed by apair of rollers having a suitable covering such as rubber or plastic,from an entrance into the area between the the chambers. A developingmedium, such as an ammonia-water vapor mixture, is supplied from eachchamber under pressure along the path of motion of the paper, to theupper and lower portions of the paper so that the paper is iloated on adeveloping medium as it moves from entrance to exit. Another pair ofrollers, similar to the ones located at the entrance, are located at theexit to lead the developed paper from the area between the chambers.

The developing medium is drawn out of the area between the chambers byducts located near the exit and is continuously recirculated by a blowerwhich supplied it under some positive pressure to each of the chambersfor distribution above and beneath the paper. A gas generator or mixerfor the ammonia-water vapor mixture is provided which includes a closedvessel, supplied with a heater,to which either anhydrous or aqueousammonia can be supplied. The closed vessel is connected to a water lvelvessel which in turn is connected to a water pump which establishes alevel of water in the water vessel and thereby establishes a level ofwater in the closed vessel. The control of the mixture, that is,controlling the replacement of the water vapor and ammonia as it isremoved from the gas generator, can of course be accomplished inaccordance with other previously known arrangements, for example, usingfloats, chemical sensing controls and the like.

Accordingly, an object of the invention is to provide a developingapparatus in which sensitized material can be contacted by thedeveloping medidum uniformly and over the entire area thereof.

Another object of the invention is to provide a developing apparatus inwhich the sensitized material is supported by the developing mediumwhile being transported therethrough.

A further object of the invention is to provide a developing apparatuswhich can use either aqueous or anhydrous ammonia as the developingmedium.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawings wherein:

FIG. 1 illustrates the developing apparatus, partly broken away, partlyin pictorial, and partly in schematic form;

FIG. 2 is a schematic sectional view along lines 2-2 of FIG. l, omittingunessential elements; and

FIG. 3 is a fragmentary sectional view along lines 3-3 of FIG. l.

Referring now to the drawings, wherein like reference charactersdesignate like or corresponding parts throughout the several views,there is shown in FIGS. l and 2 a sheet of sensitized paper 10, whichmay be a cut sheet, or a continuous web from a roll, which is fedbetween a pair of rollers 11, 11 suitably secured in bearings (notshown) so that the rol-1ers normally contact each other. They tightlygrip the paper 10 fed therebetween and in the absence of any paper forma sealing contact.

A housing 12, as more clearly viewed in FIG. 2, has top and bottom walls13, 14, end walls 15, 15', 16, 16 and inner walls, 20 and 20. Theinterior of the housing thus formed has a pair of box like closedchambers 19, 19. The entrance to the area between the chambers 19, 19 issealed by the rollers 11, 11 and by wipers 21, 21 which engage therollers at a point remote from their mutual contact, so as to seal thisarea against the outside atmosphere. The inner walls 20, 20' areperforated with a plurality of sized apertures as seen at 22, 22 todistribute the developing medium along the path of travel of the paper.The exit from the housing is formed by rollers 18, 18 which togetherwith wipers 28, 28 seal the area between the chambers 19, 19 in the samefashion as wipers 21, 21 and the rollers 11, 11.

Located within the chambers 19, 19 are perforated tubes 24, 24 which arecoupled to a compressor 38 and supply developing medium from thecompressor to the chambers 19, 19 as will be more fully described. Aportion of chambers 19, 19 close to the exit rollers 18, 18 ispartitioned ott as seen at 25 and 25', respectively, to form exhaustduct connections which are coupled to the cornpressor for recirculatingthe developing medium.v The boxlike chambers 19, 19 are wider than thepaper 10 for which ythe apparatus is designed, so that developing mediumintroduced to the upper and lower box-like chambers 19 and 19 can passaound the edges of the paper 10l and between edges 57 and 57 of endwalls 20 and 20', respectively, and a housing frame 56 (shown in FIG. 3)to the outlet ducts 25, 25.

If desired, heaters in the form of electrical heating elements may alsobe used in the 1box-like chambers 19, 19. Four such heaters are shown inFIG. 1 at 26a-26d.

The entire system is best seen in FIG. 1. Anhydrous ammonia is passedthrough an input tube 30 into a duct 53 which has an opening 53' leadingto a `gas generator or mixing chamber 31. Generator 31 is partly filledwith water from a supply tube 32 entering at the bottom from a liquidlevel vessel 33; Iwhereby the liquid level in generator 31 and in vessel33 are always at the same level. The level of the vessel 33 ismaintained at a preselected height with the aid of a pump 34 pumping-water through a pipe 54, a valve 35 and a pipe 55 which leads into thetop of the level vessel 33. Excess uid in the level vessel 33 isconducted to a sump 43 via a pipe 47, a valve 36 and a pipe 51, therebymaintaining the preselected level in vessel 33. The sump 43 supplieswater for the pump 34 through a supply pipe 56. When aqueous ammonia isselected by a user, it is introduced into duct S3 through a pipe 40 andthe excess fluid from generator 31 is conducted through pipes 47 and 48and through valve 44 and pipe 49 to a drain vessel 45. A pipe 41 inlevel vessel 33 and a pipe 46 in drain vessel 45 vent their respectivevessels to atmospheric pressure.

In order to bring the ammonia and the Water to the proper temperature,mixing chamber 31 is provided with heater coils 37 which, like theheaters 26a-26d can be connected to a source of electrical power, notshown.

As previously mentioned, generator 31 is connected at 53' to the duct 53which lhas a pair of outlet tubes, one connecting with supply tube 24and the other with supply tube 24. The inlet to Ithe duct 53 is from ablower 38 which exhausts developing medium from chamber outlet ducts 25,25 to the blower inlet duct 40 as schematically indicated by arrows 39and 39'. The connection of duct 25 to the duct 40 of blower 38 has beenshown in phantom in FIG. 1.

The choice of whether to use anhydrous ammonia or aqueous ammonia is upto the user. When anhydrous ammonia is used the valves 35 and 36 areopened and the pump 34 is operated to maintain the preselected Waterlevel in vessel 33 which thereby maintains the same level in generator31 as previously described. Passing anhydrous ammonia from pipe 30 overthe water in generator 31, while supplying heat through heater coils 37will cause a water-vapor ammonia mixture to exit through opening 53 andbe supplied under positive pressure by blower 38 to ducts 24,124. Thewater vapor ammonia mixture will escape through holes 22, 22 to float asheet of paper 10 introduced between the rollers 11, 11 in its passagethrough the machine. The ammonia-water vapor mixture can be retained atthe proper temperature by means of the aforementioned heaters 26a-26d.The vapor mixture is again recirculated by the blower 38, and brought tothe proper temperature and humidity content by means of heater 37 andthe continuous supply of anhydrous ammonia. If the water level ingenerator 31 drops, for example, due to absorption of water by thepaper, pump 34 will continue to supply additional Water to vessel 33which provides Water via pipe 32 to restore the level in generator 31.

If the user chooses to use aqueous ammonia, the valves 35 and 36 areclosed and valve 44 is opened. In this case, the supply of water may begreater than that absorbed by the paper or used in the developingprocess. Therefore, in order to maintain the level within generator 31constant and at the proper height, pump 34 is not used and excess fluidfrom level vessel 33 is drained through pipes 47 and 48 through valve 44and pipe 49 to the drain vessel 45.

An alternate way of supplying ammonia fumes, that is, a mixture of watervapor and ammonia to the developing surface, is to utilize only a singletube 24 or 24', with transfer slots at the lateral edges of theperforated sheets 20, 20 and thereby to deliver fumes to both chambers19 and 19. The remainder of the travel of the vaporammonia mixture willbe similar to that previously described-air is forced by blower 38 topass through the generator 31 Where water vapor caused by heating thewater, by means of heater 37, is conditioned with ammonia, to eithersupply in anhydrous form through tube 4 30, or in aqueous form throughtube 40. Ammoniated and heated vapor under pressure is then made toenter the developer through either one of tubes 24 or 24.

It should be understood that the length between the entrance and exit ofthe area between the chambers is smaller than the length of thesensitized paper to be developed. If, however, it is desirous to usepaper with a length shorter than the distance between the entrance andexit, a pair of rollers may be inserted in this area to guide andsupport the shorter length of paper.

The foregoing disclosure relates to only a preferred embodiment of theinvention, and that it is intended to cover all changes andmodifications of the example of the invention herein chosen for thepurposes of the disclosure, which do not constitute departures from thespirit and scope of the invention.

The invention claimed is:

1. In developing apparatus having a developing chamber, in which a sheetof paper is introduced into said developing chamber, a mixing chamberhaving a pair of inlet means, one adapted for supply of anhydrousammonia and the other for supply of aqueous ammonia; a heater in saidmixing chamber; vessel means containing a liquid and connected to saidmixing chamber for establishing a predetermining liquid level in saidmixing chamber; a blower, in communication with said mixing chamber anddelivering a water vapor-ammonia mixture therefrom; and means supplyingsaid mixture of water vapor and ammonia under pressure into saiddeveloping chamber to float the paper thereon.

2. Apparatus as recited in claim 1 wherein a pump in communication withsaid vessel means provides water to said vessel supply means determinedin proportion to the use of the water vapor-ammonia mixture and thesupply of anhydrous ammonia.

3. An improved developing apparatus including a gaseous developingmedium introduced under pressure to develop and support an exposed sheetof sensitized paper, the improvement comprising a mixing chamber forammonia and water in communication with a fluid inlet means disposedadjacent a paper entrance means for introducing said ammonia and waterinto a pair of spaced apart, vertically disposed chambers respectively;a first supply tube for leading anhydrous ammonia into said mixingchamber; a second supply tube for leading aqueous ammonia into saidmixing chamber; a heater in said mixing chamber; a supply vessel forwater; and means interconnecting said mixing chamber and said watersupply vessel whereby the fluid level in said mixing chamber ismaintained at the same level as said Water supply vessel.

4. Developing apparatus as recited in claim 3 including a pump whereinthe improvement comprises disposing said pump in uid circuit relationwith an interconnecting means interconnecting a mixing chamber and awater supply vessel to establish, selectively, the level of uid in saidwater supply vessel.

References Cited 'UNITED STATES PATENTS 3,048,383 8/1962 Champlin 34-156X 3,071,866 1/1963 Mangus 34-155 X 3,147,687 9/ 1964 Halden 95-89 X3,192,846 7/ 1965 Wright 95-94 3,308,555 3/1967 Kruger 34-155 3,330,1897/1967 Vil 95-89 X NORTON ANSHER, Primary Examiner.

C. E. SMITH, Assistant Examiner.

U.S. Cl. X.R.

